Our garden club met in a cold Centennial Hall, surrounded by several feet of snow outside from a late winter storm. More than two dozen hardy folks gathered around the small heater, cups of warm coffee and tea in hand, to share their winter adventures and hopes of gardening adventures yet to be.
After a brief business meeting, our guest speaker, Jeff Gillis of WellTree, Inc of Brunswick, talked about pruning trees and shrubs. Why should we prune? To keep the plant structurally sound, we remove deadwood and branches that interfere with the plant’s ability to stand soundly, with good air circulation. Pruning is done for the health of the plant, and the health and safety of people around it. The foliage on the plant supplies food to the plant. Removal of too much foliage will stress the plant, and perhaps generate more growth.
Timing of pruning is important. While deadwood can be removed at any time, live wood must be removed at specific times. Pruning too late in the fall can stimulate new growth that will be subjected to winter’s cold before the growth has hardened, causing damage and death to the new growth. Pruning in the early spring on plants that flower in early spring will remove the flowering buds, reducing the flowers and fruits that would normally grow. Knowing the plant’s flowering time helps determine the pruning time. It is best to wait until lilacs have bloomed before pruning them back in late Spring. Pruning hydrangeas depends very much on what type of hydrangea you have. Apple trees should be pruned in late winter before new growth begins. Willows should be done just after their flowers are spent.
Removing too much foliage at one time can stimulate to appearance of “water sprouts” (suckers). Plan ahead, removing no more than a quarter of the plant’s foliage in one year. If the suckers appear, remove those a few at a time as well, or even more will shoot out.
Proper tools aid in good pruning. By-pass pruning shears are a good start. When using them, keep the blade facing the plant. A good pruning saw that flips open and closed is a valuable tool as well. Pole pruners are handy, but can be heavy and awkward. Aluminum pole pruners are available, but a bit pricey.
In other tree talk, Jeff addressed the stress on trees from winter moth caterpillars and brown tail moth caterpillars, as well as drought. The combination of a dry summer in 2016, plus repeated defoliation by various caterpillars puts trees in jeopardy, and many may not survive repeated attacks. The good news is that fewer trees will produce less food for the caterpillars, reducing the numbers of moths. If a homeowner wants trees sprayed for the moths, contact a licensed arborist who will abide by the pesticide ordinances in town.